Uber has just hired a NASA expert to build out its vision for flying cars Monday. Mark Moore, a 30-year veteran of the space agency with expertise in using electric motors to get a vehicle airborne, will help the ride-hailing giant execute on an expansive white paper it released last fall on developing VTOL (vertical take-off and landing) vehicles.

"Uber continues to see its role as a catalyst to the growing developing VTOL ecosystem," Nikhil Goel, Uber's head of product for advanced programs, said in a statement. "We're excited to have Mark join us to work with companies and stakeholders as we continue to explore the use case described in our white paper."

Moore said he was leaving NASA Langley Research Center a year before his retirement benefits kick in to throw his lot in with Uber CEO Travis Kalanick because he was convinced that no other company was in a "stronger position to be the leader for this new ecosystem and make the urban electric VTOL market real,” he told Bloomberg.

Uber's long treatise on flying cars, which Moore consulted on, suggested the company was aiming its sights not on building a prototype but rather on developing the technology that would be integral to such a craft.

That includes figuring out how to guarantee battery life and limit noise pollution. Air space regulation issues aside, the ultimate goal of a VTOL project is to shorten commutes in the world's most congested cities.

"Just as skyscrapers allowed cities to use limited land more efficiently, urban air transportation will use three-dimensional airspace to alleviate transportation congestion on the ground," the Uber white paper reads. "A network of small, electric aircraft that take off and land vertically, will enable rapid, reliable transportation between suburbs and cities and, ultimately, within cities."

Uber isn't flying solo in this quest. Google co-founder Larry Page has invested $100 million in two companies — Zee.Aero and Kitty Hawk — pursuing VTOL projects, according to Bloomberg. Other market entrants include Joby Aviation, Terrafugia and AeroMobil, a Slovakian company that has been testing its car-sprouts-wings prototype since 2014.

The technological feasibility of flying vehicles aside, the biggest issue for the transportation initiative would seem to be regulatory. The Federal Aviation Administration already has its hands full grappling with evolving drone rules. Companies such as Amazon have been testing drone delivery programs.

The FAA’s first comprehensive drone regulations took effect in August, allowing flights of drones weighing up to 55 pounds up to 400 feet in the air in uncrowded areas during the day within sight of the pilot. But drone operators are now concerned about that a general rolling back of federal regulations by the Trump administration will negatively impact their ability to fly.

That said, Uber officials pointed out in the white paper that dense urban areas such as Sao Paulo, Brazil, already use air space for helicopters flights operating under visual flight rules, an approach that VTOLs could also take.

But hurdles remain for Moore and others working in the space. And self-driving car efforts also are siphoning off financial and human capital.

Uber sounded an excited if cautious note in its white paper: "There are promising initiatives underway, but they will play out over many years and their pace may ultimately bottleneck growth."